Have you ever flown on an airplane during wintery weather? There’s a good chance you may have seen mechanics deicing your plane with a misty fluid before your flight. Deicing is a critical maintenance process of removing snow, ice, or frost from an aircraft’s surface. Aircraft are designed to fly with clean surfaces, and during colder periods of the year, icy materials can build up, disrupt airflow, and interfere with a safe take-off.

Deicing is a process that all airliners must be familiar with. For many areas of the US, deicing can be a necessary precaution for 3/4ths of the year!

What Is Used to Deice Aircraft?

Deicing fluid is a glycol-based substance sprayed on an aircraft during typical deicing processes. Deicing fluids are sprayed on hot and come in four main types:

Type I – Combined with water in a 55:45 mixture for low viscosity. Type I is sprayed on hot at a high pressure to remove ice quickly—typically dyed orange.

Type II – Combined with water in a 75:25 mixture, resulting in a jelly-like feel. This fluid is applicable for both deicing and anti-icing measures. Typically clear/straw in appearance.

Type III – Designed as a middle-point between Type I and Type II ratios.

Type IV – Not diluted with water resulting in a highly viscous substance, most applicable for icing prevention. Dyed emerald green.

Type I is the deicing fluid most used during ground crew preparations and the fluid is blasted on at a hot 140-150 degrees Fahrenheit by dedicated deicing vehicles. Areas hit with this fluid include the fuselage top centerline, wings, and horizontal stabilizers.

After deicing, the ground crew may apply anti-icing fluid onto the plane. Anti-icing fluid has a higher glycol concentration than standard deicing fluid and is unheated, undiluted, and thickened. This is to help prevent the future build-up and accumulation of ice while on the ground. When a plane accelerates for take-off, anti-icing fluid will naturally run off and leave a clean surface for proper flight.

Manual Deicing

Manual deicing is deicing through mechanical movements like pushing or scraping. This method is great for smaller aircraft or if fluid is unavailable for use. The FAA recommends using brooms, brushes, wing/propeller covers, or air blowers during the manual deicing process. The manual process can be highly effective at removing residue, but mechanics should be careful not to brush ice or frost contamination into gaps or cavities of the aircraft.

In-flight Deicing Systems

Anti-icing fluids are ineffective during flight, so aircraft are equipped with in-flight systems that prevent icy build-up during operation.

Modern jet aircraft can have “bleed air systems” installed, which are structural routings that disperse heat from the engine throughout the plane to keep surfaces heated.

Another common ice prevention system is the usage of deicing boots. Deicing boots are rubber coverings or balloons that can be inflated during flight to break up ice on the structure. These are commonly placed on wings, tails, engines, propellors, and fan blades.

Mechanics deicing a plane at Cape Air

Mechanics manually deicing a plane.

Deicing Advancements

While modern deicing methods are very effective, deicing is by no means a solved process, especially regarding the necessity of deicing fluid and reapplication. Advancements are being researched by many facilities to improve in these fields.

An unfortunate side effect of deicing liquids is their negative environmental qualities. These contaminants can spread into surface level waters and force fish and other aquatic organisms out of the ecosystem. Research is underway to find less environmentally toxic non-glycol alternatives.

New “hybrid” deicing technology by Invercon-NEI is currently in the works to improve ice build-up prevention (as of Dec 2021). This technology, tested at NASA’s Icing Research Tunnel, utilizes an anti-ice coating by NEI that creates a lubricating surface that can reduce the adhesion effectiveness of ice by up to 80%! This anti-ice coating can be retrofitted onto existing aircraft through spraying, and paints a bright future for anti-ice measurements.

Become an Aviation Maintenance Technician!

Deicing is one of the many responsibilities of an aviation maintenance technician (AMT). Technicians are essential to the smooth operation of the aviation industry, with approximately 626,000 projected to be needed worldwide over the next 20 years!

If you’re interested in pursuing a career in aviation, fill out the form below to get in contact with National Aviation Academy!